A few more suggestions that I am sure you are aware of:
1) Text selection in mail, e.g. to copy a link, a phone, an address etc.
2) If 1) cannot be done, at least the ability to edit quote in reply.
3) Smart parsing of phone number/address in the mail content so user can directly dial a number/open an address in Map.

I am using Beta2 fw on N950 by the way (N9 is not available where I live).